1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _ASM_GENERIC_BUG_H 3 #define _ASM_GENERIC_BUG_H 4 5 #include <linux/compiler.h> 6 7 #define CUT_HERE "------------[ cut here ]------------\n" 8 9 #ifdef CONFIG_GENERIC_BUG 10 #define BUGFLAG_WARNING (1 << 0) 11 #define BUGFLAG_ONCE (1 << 1) 12 #define BUGFLAG_DONE (1 << 2) 13 #define BUGFLAG_TAINT(taint) ((taint) << 8) 14 #define BUG_GET_TAINT(bug) ((bug)->flags >> 8) 15 #endif 16 17 #ifndef __ASSEMBLY__ 18 #include <linux/kernel.h> 19 20 #ifdef CONFIG_BUG 21 22 #ifdef CONFIG_GENERIC_BUG 23 struct bug_entry { 24 #ifndef CONFIG_GENERIC_BUG_RELATIVE_POINTERS 25 unsigned long bug_addr; 26 #else 27 signed int bug_addr_disp; 28 #endif 29 #ifdef CONFIG_DEBUG_BUGVERBOSE 30 #ifndef CONFIG_GENERIC_BUG_RELATIVE_POINTERS 31 const char *file; 32 #else 33 signed int file_disp; 34 #endif 35 unsigned short line; 36 #endif 37 unsigned short flags; 38 }; 39 #endif /* CONFIG_GENERIC_BUG */ 40 41 /* 42 * Don't use BUG() or BUG_ON() unless there's really no way out; one 43 * example might be detecting data structure corruption in the middle 44 * of an operation that can't be backed out of. If the (sub)system 45 * can somehow continue operating, perhaps with reduced functionality, 46 * it's probably not BUG-worthy. 47 * 48 * If you're tempted to BUG(), think again: is completely giving up 49 * really the *only* solution? There are usually better options, where 50 * users don't need to reboot ASAP and can mostly shut down cleanly. 51 */ 52 #ifndef HAVE_ARCH_BUG 53 #define BUG() do { \ 54 printk("BUG: failure at %s:%d/%s()!\n", __FILE__, __LINE__, __func__); \ 55 barrier_before_unreachable(); \ 56 panic("BUG!"); \ 57 } while (0) 58 #endif 59 60 #ifndef HAVE_ARCH_BUG_ON 61 #define BUG_ON(condition) do { if (unlikely(condition)) BUG(); } while (0) 62 #endif 63 64 #ifdef __WARN_FLAGS 65 #define __WARN_TAINT(taint) __WARN_FLAGS(BUGFLAG_TAINT(taint)) 66 #define __WARN_ONCE_TAINT(taint) __WARN_FLAGS(BUGFLAG_ONCE|BUGFLAG_TAINT(taint)) 67 68 #define WARN_ON_ONCE(condition) ({ \ 69 int __ret_warn_on = !!(condition); \ 70 if (unlikely(__ret_warn_on)) \ 71 __WARN_ONCE_TAINT(TAINT_WARN); \ 72 unlikely(__ret_warn_on); \ 73 }) 74 #endif 75 76 /* 77 * WARN(), WARN_ON(), WARN_ON_ONCE, and so on can be used to report 78 * significant issues that need prompt attention if they should ever 79 * appear at runtime. Use the versions with printk format strings 80 * to provide better diagnostics. 81 */ 82 #ifndef __WARN_TAINT 83 extern __printf(3, 4) 84 void warn_slowpath_fmt(const char *file, const int line, 85 const char *fmt, ...); 86 extern __printf(4, 5) 87 void warn_slowpath_fmt_taint(const char *file, const int line, unsigned taint, 88 const char *fmt, ...); 89 extern void warn_slowpath_null(const char *file, const int line); 90 #define WANT_WARN_ON_SLOWPATH 91 #define __WARN() warn_slowpath_null(__FILE__, __LINE__) 92 #define __WARN_printf(arg...) warn_slowpath_fmt(__FILE__, __LINE__, arg) 93 #define __WARN_printf_taint(taint, arg...) \ 94 warn_slowpath_fmt_taint(__FILE__, __LINE__, taint, arg) 95 #else 96 extern __printf(1, 2) void __warn_printk(const char *fmt, ...); 97 #define __WARN() __WARN_TAINT(TAINT_WARN) 98 #define __WARN_printf(arg...) do { __warn_printk(arg); __WARN(); } while (0) 99 #define __WARN_printf_taint(taint, arg...) \ 100 do { __warn_printk(arg); __WARN_TAINT(taint); } while (0) 101 #endif 102 103 /* used internally by panic.c */ 104 struct warn_args; 105 struct pt_regs; 106 107 void __warn(const char *file, int line, void *caller, unsigned taint, 108 struct pt_regs *regs, struct warn_args *args); 109 110 #ifndef WARN_ON 111 #define WARN_ON(condition) ({ \ 112 int __ret_warn_on = !!(condition); \ 113 if (unlikely(__ret_warn_on)) \ 114 __WARN(); \ 115 unlikely(__ret_warn_on); \ 116 }) 117 #endif 118 119 #ifndef WARN 120 #define WARN(condition, format...) ({ \ 121 int __ret_warn_on = !!(condition); \ 122 if (unlikely(__ret_warn_on)) \ 123 __WARN_printf(format); \ 124 unlikely(__ret_warn_on); \ 125 }) 126 #endif 127 128 #define WARN_TAINT(condition, taint, format...) ({ \ 129 int __ret_warn_on = !!(condition); \ 130 if (unlikely(__ret_warn_on)) \ 131 __WARN_printf_taint(taint, format); \ 132 unlikely(__ret_warn_on); \ 133 }) 134 135 #ifndef WARN_ON_ONCE 136 #define WARN_ON_ONCE(condition) ({ \ 137 static bool __section(.data.once) __warned; \ 138 int __ret_warn_once = !!(condition); \ 139 \ 140 if (unlikely(__ret_warn_once && !__warned)) { \ 141 __warned = true; \ 142 WARN_ON(1); \ 143 } \ 144 unlikely(__ret_warn_once); \ 145 }) 146 #endif 147 148 #define WARN_ONCE(condition, format...) ({ \ 149 static bool __section(.data.once) __warned; \ 150 int __ret_warn_once = !!(condition); \ 151 \ 152 if (unlikely(__ret_warn_once && !__warned)) { \ 153 __warned = true; \ 154 WARN(1, format); \ 155 } \ 156 unlikely(__ret_warn_once); \ 157 }) 158 159 #define WARN_TAINT_ONCE(condition, taint, format...) ({ \ 160 static bool __section(.data.once) __warned; \ 161 int __ret_warn_once = !!(condition); \ 162 \ 163 if (unlikely(__ret_warn_once && !__warned)) { \ 164 __warned = true; \ 165 WARN_TAINT(1, taint, format); \ 166 } \ 167 unlikely(__ret_warn_once); \ 168 }) 169 170 #else /* !CONFIG_BUG */ 171 #ifndef HAVE_ARCH_BUG 172 #define BUG() do {} while (1) 173 #endif 174 175 #ifndef HAVE_ARCH_BUG_ON 176 #define BUG_ON(condition) do { if (condition) BUG(); } while (0) 177 #endif 178 179 #ifndef HAVE_ARCH_WARN_ON 180 #define WARN_ON(condition) ({ \ 181 int __ret_warn_on = !!(condition); \ 182 unlikely(__ret_warn_on); \ 183 }) 184 #endif 185 186 #ifndef WARN 187 #define WARN(condition, format...) ({ \ 188 int __ret_warn_on = !!(condition); \ 189 no_printk(format); \ 190 unlikely(__ret_warn_on); \ 191 }) 192 #endif 193 194 #define WARN_ON_ONCE(condition) WARN_ON(condition) 195 #define WARN_ONCE(condition, format...) WARN(condition, format) 196 #define WARN_TAINT(condition, taint, format...) WARN(condition, format) 197 #define WARN_TAINT_ONCE(condition, taint, format...) WARN(condition, format) 198 199 #endif 200 201 /* 202 * WARN_ON_SMP() is for cases that the warning is either 203 * meaningless for !SMP or may even cause failures. 204 * This is usually used for cases that we have 205 * WARN_ON(!spin_is_locked(&lock)) checks, as spin_is_locked() 206 * returns 0 for uniprocessor settings. 207 * It can also be used with values that are only defined 208 * on SMP: 209 * 210 * struct foo { 211 * [...] 212 * #ifdef CONFIG_SMP 213 * int bar; 214 * #endif 215 * }; 216 * 217 * void func(struct foo *zoot) 218 * { 219 * WARN_ON_SMP(!zoot->bar); 220 * 221 * For CONFIG_SMP, WARN_ON_SMP() should act the same as WARN_ON(), 222 * and should be a nop and return false for uniprocessor. 223 * 224 * if (WARN_ON_SMP(x)) returns true only when CONFIG_SMP is set 225 * and x is true. 226 */ 227 #ifdef CONFIG_SMP 228 # define WARN_ON_SMP(x) WARN_ON(x) 229 #else 230 /* 231 * Use of ({0;}) because WARN_ON_SMP(x) may be used either as 232 * a stand alone line statement or as a condition in an if () 233 * statement. 234 * A simple "0" would cause gcc to give a "statement has no effect" 235 * warning. 236 */ 237 # define WARN_ON_SMP(x) ({0;}) 238 #endif 239 240 #endif /* __ASSEMBLY__ */ 241 242 #endif 243